Emotional well-being reflects an individual's global evaluation of his or her life as a whole. Well-being is thought to be influenced by a variety of factors in a person's life, including life events, life circumstances, and a number of personality characteristics. Because these characteristics may change in systematic ways over the course of the life span, age differences in well-being can be expected. Yet existing studies are limited in their ability to resolve debates about the nature of these changes. In addition, research shows that emotions are not simply reactive. Recent theoretical advances suggest that emotional well-being may be functional and adaptive. Thus, high levels of well-being may promote successful aging. In the proposed project, the investigators will: (a) document changes in well-being across the life span, (b) test hypotheses about the effects of well-being on occupational outcomes, and (c) test hypotheses about the effects of well-being on risk of mortality. Data from the German Socio-Economic Panel Study (a nationally representative longitudinal study in which over 35,000 respondents aged 16 to 102 were surveyed yearly for up to 20 years) will be analyzed. Growth modeling will be used to assess the extent to which well-being changes over time and across cohorts. Regression analyses will be used to assess the extent to which initial levels of well-being predict positive occupational outcomes. Survival analyses will be used to determine whether happy individuals have a lower risk of mortality. In all analyses, variables related to health and work will be included to help elucidate the processes involved in these effects. Results from this study will provide one of the most comprehensive pictures of well-being change over the course of the life span. In addition, this study will inform both basic theories of emotion and more applied theories about mechanisms that may prevent mental and physical health declines over the course of the life span.